Hi fellas!

Just cracked open a C34 I bought a couple weeks back, and found something I haven't seen before. I'm hoping you cats can give me the straight skinny on this.

Original JBL 'factory' C34 in Walnut. It does not appear that the cabinet has ever had the grill off, definately not the speaker baffle. Grill logo is brass colored 'exclamation' with jbl in the dot, and "signature" off to the right.
N1200 has "pointer" style plastic, or bakelite HF knob (not round knob found on later versions).
Signature Series 130A (grey) with foil id tag on magnet.
Horn is 175DLH. Black wrinkle.
Now here's the part I've never seen before... horn driver (model 175) label is not typical foil, but rather is a large oval piece of plastic (black on top/white underneath) which has all the data cut into the face. Logo has single "L" in exclamation dot, and "Jim Lansing - Signature" on the sides. The paint finish is black/wrinkle. Red wax seals on either side of id tag have capital "L" in cursive stamped into them.

N1200 serial #: 3907
130A ser. #: 14161
175 ser. #: 6133

Looking at the library catalogs I noticed the logo changes between 1952, and 1955, then again in 1957?.
Can I assume, based solely on what lay before me that this C34 was put together most likely in late 1956, or early 1957 using components left over with the older style id, and components with the newer id labels?
If not what do you think?
Is the 175 driver noted above of any special significance, or does it merely sport an older style id tag?
Are drivers with this style id tag scarcer? More/less desireable for some reason? Are they accorded a premium over later versions?

Any info on this, including approx. date of manufacture, etc. would be much appreciated. I bought this folded horn with the specific intention of reselling it, and was just a little surprised by the tag on the 175. Thanks in advance.

Regards,
Mike

PS: Is there some formula within the serial number, or web location where one could look up serial numbers to approximate the age of a particular JBL component?